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Phantom Braking

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I have an M3LR vision-only car. Drive from Dallas to Shreveport today on NOA. No phantom braking. I know some cars have big issues with this, and my car was originally one of them. But since the beginning of the year, I rarely experience it. So, the software is capable of reliable operation. But why some cars are better than others is a mystery. Best I know is to recalibrate the cameras of I do experience a PB event.
 
Sadly, at the moment it seems the only thing you can do is not use it or accept that you are going to have to be ready to hit the accelerator when using TACC.

Really hoping the recent investigations into this behavior will force Tesla to at least give us a dumb cruise control while they try and get this stuff working properly.
Dumb cruise control doesn’t brake, I had it in a loaner and was depressed driving it.
 
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I have had multiple issues with phantom braking since i purchased my 22m3lr 2 months ago. this past weekend my wife and i went out to visit our son in Wichita KS. I probably had 3 of 4 braking incidences on the way to Wichita. Unfortunately is was dark on the way home. On a 2 lane highway at 65mph i had 30 to 40 phantom braking issues. This would happen if i was using cruise control or auto steer. probably 1 out of 5 cars or trucks would slow the car down. It was manageable if i kept my foot on the gas and powered through it, but the warning tones went off at lease 20 times. I have taken to car Tesla for service and was told that this was something that i need to get use to with the vehicle. i was told that this will get better with time. Like i said it is manageable during the day but down right scary at night. Does anyone have a solution to this problem?
thanks
 
I have had multiple issues with phantom braking since i purchased my 22m3lr 2 months ago. this past weekend my wife and i went out to visit our son in Wichita KS. I probably had 3 of 4 braking incidences on the way to Wichita. Unfortunately is was dark on the way home. On a 2 lane highway at 65mph i had 30 to 40 phantom braking issues. This would happen if i was using cruise control or auto steer. probably 1 out of 5 cars or trucks would slow the car down. It was manageable if i kept my foot on the gas and powered through it, but the warning tones went off at lease 20 times. I have taken to car Tesla for service and was told that this was something that i need to get use to with the vehicle. i was told that this will get better with time. Like i said it is manageable during the day but down right scary at night. Does anyone have a solution to this problem?
thanks
I just got back from a 500 miles trip yesterday, clear day and empty divided highway with 2021 M3LR and 2022.8.3. I had around one PB incident every 20 minutes. My passenger kept complaining about slamming on the brakes to the point where I just turned it off.
I wish the car just had the option of standard cruise control. I now Consider this unusable and stressful just waiting for the car to slam on the brakes for no reason. I will look into camera calibration, but I wonder if it has to do with the sun shining on the camera?
 
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I have an M3LR vision-only car. Drive from Dallas to Shreveport today on NOA. No phantom braking. I know some cars have big issues with this, and my car was originally one of them. But since the beginning of the year, I rarely experience it. So, the software is capable of reliable operation. But why some cars are better than others is a mystery. Best I know is to recalibrate the cameras of I do experience a PB event.
I wonder if cars with FSD are better? I just have TACC and it’s terrible with 2022.8.3 Even on empty highways during the day.
 
I wonder if cars with FSD are better? I just have TACC and it’s terrible with 2022.8.3 Even on empty highways during the day.
No one really knows if/how the various systems interact with each other. I will say that I’m on FSD beta and with the latest update (FSD 10.11.2/2022.4.5.21) and PB definitely seems to be better. Not perfect but better. I don’t know if that’s from the FSD code or if they also tweaked the TACC code or maybe both. I’ll also say that I’ve driven cars with both radar and vision-based adaptive cruise that function well, so the argument that a vision-based TACC will never be as good as a radar-based system is wrong. It’s possible, Tesla just needs to fix their algorithms.
 
No one really knows if/how the various systems interact with each other. I will say that I’m on FSD beta and with the latest update (FSD 10.11.2/2022.4.5.21) and PB definitely seems to be better. Not perfect but better. I don’t know if that’s from the FSD code or if they also tweaked the TACC code or maybe both. I’ll also say that I’ve driven cars with both radar and vision-based adaptive cruise that function well, so the argument that a vision-based TACC will never be as good as a radar-based system is wrong. It’s possible, Tesla just needs to fix their algorithms.
I really wish they had an option for turning off the traffic aware portion and just have regular cruise control. I turned off all my safety options like lane keeping and auto emergency braking thinking that might help, but it didn’t. My 2015 MS with autopilot worked a lot better. I will try the camera calibration and hope for another software update.
 
I really wish they had an option for turning off the traffic aware portion and just have regular cruise control. I turned off all my safety options like lane keeping and auto emergency braking thinking that might help, but it didn’t. My 2015 MS with autopilot worked a lot better. I will try the camera calibration and hope for another software update.
I did some experimenting with turning the various systems off a couple months ago. It seemed to help but still didn’t completely eliminate the problems. I also used to think that it would be nice to have ‘dumb’ cruise control and then we took a trip in our 10 year old odyssey with dumb cruise and even with its faults I found TACC to be better.

I agree - It’s aggravating that Tesla can’t match the functionality of a $20k honda civic, much less other cars in its class. We can only hope they bring it up to snuff with software updates.
 
But it isn’t true. The safety score is not affected when you are driving on auto
You sure about this? Want to retract your statement?

 
You sure about this? Want to retract your statement?

You really should read articles before you link to them. When they don't support your argument you look like an idiot.
 
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Just got back from a 5000 miles round trip and I'd like to report. First 3000 we had AP and TACC on the vast majority of the time. On the way back we were pulling a trailer so TACC only. We had some slowdowns. I wouldn't say braking because they were never that harsh. More like taking your foot off of the accelerator pedal.

2 of them were when a vehicle pulled in front of us and the car slowed where I knew it didn't need to because the other vehicle was accelerating. 2 were where there was a visible mirage on the road ahead of us. Once, it was a cloud shadow on the road. There also were times when there were hash marks on the road due to construction and it was unique and I didn't know why they were there, either.

We were on 2022.8.3 on the way out and 2022.12.3.1 on the way back. Most of the events were on the way back (TACC only).
 
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In the 45K miles I've driven my 2020 M3, I haven't experienced any dramatic phantom braking. I've had plenty of mild slowdowns. I've been wondering about why things might be different for me. Here's some brainstorming about why some drivers see lots of phantom braking while I do not.

1. Something about the combination of settings that I have. That is, Automatic Emergency Braking, Forward Collision Warning, Lane Departure, etc.
2. I usually have my foot near the accelerator and press it if the car starts to slow down (as it does for blinking yellows). Perhaps my lightning reflexes catch phantom braking before it occurs?
3. Something different about my car's hardware (sensors?).
4. I drive more conservatively (rarely more than a few MPH above the speed limit).
5. Some are interpreting the slowdown more dramatically. For example, "slamming on the brakes" rather than "slows down a lot."

Related to option 5, I've attached an interesting video. It shows a car slowing from 69 to 47 in a few seconds. That's pretty dramatic, and I don't think I've seen anything like that. Here are two observations:

1. He's going 69 MPH on a two-lane road. Similar roads around here rarely have a limit higher than 55. Could that be relevant.
2. At 1:39 in that video, the car slows from 63 MPH to 48 MPH. He says that the car "almost tries to come to a full stop."

Here's another video in which the driver calls it "maybe" phantom braking, yet the speed only dropped from 90 km/hr to 87 km/hr:
.

Another where car slows from 66 to 57 and the driver says "the car just slammed on the brakes."

What do you think explains why some see phantom braking and others do not?
 
I think some of it is location related. If your normal drive has some geography that AP doesn't like, or a map data error, the car may regularly misbehave and you think the car is trash.

I think some of it is a lack of understanding of why the car will slow down intentionally. Like for curves or slow moving traffic in an adjacent lane. Surface streets crossing a freeway and exit speeds sometimes caused slowdowns in an erroneous but predictable way. I haven't experienced a serious no apparent cause phantom braking event for the last 25k miles or so.

I have no idea why some people's cars slam on the brakes and others don't. I put that down mostly to dramatics, but my normal braking could be termed slamming on the brakes. Some people think the suspension is too soft and some too hard, with apparently a giant performance chasm between the two the way it is described. Some people drive super chill and some drive for sport. I do drive with my foot on the accelerator just in case.

After that I have to go with camera problems, like misalignments. There seems to have been several cases of Service Center camera realignments fixing some AP problems.
 
Mine seems to most commonly do this when creating slight hills, like the car thinks we are about to go off a cliff. It has been dramatic enough to startle awake sleeping passengers, going from 80ish to mid-50s before I get my foot back on the accelerator.

Sometimes the car will go hundreds of miles with no issues, and at its worst I had to stop using Autopilot because it was doing this once every few miles.

Of note, have never had any issues with just using the cruise control (no lane keeping), other than for actual obstacles or other real concerns.

M3P, owned 36 days with 3500 miles.
 
Moderator note: This plus the next (approximately) dozen posts were merged from a thread in a different forum.

Just to add to the clamor. We experienced three closely spaced incidents of phantom braking with our Model Y while using cruise control without lane assist on highway 395 between Lone Pine and Bishop, California on Saturday 25 June. We've had the car since January 2022, and this was a (shocking) first. Haven't dared to use cruise control since. We have since updated to software version 2022.16.2. I guess we'll have to see if this took care of it. This is my first big disappointment with Tesla. My second is that it is impossible to find a way to report the issue to Tesla itself (other than the bug report which should be done on the spot). I have filed a report with NHTSA. Until the issue is fixed -- and from what I can tell, Tesla never really does fix phantom braking -- I wonder if it can be prevented by turning off emergency braking when using cruise control...?
 
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I could add that I was driving on a two-lane highway (two lanes in one direction, two lanes in the other) when the phantom breaking occurred. In the first two instances, I was in the left-hand lane and starting to overtake a car in the right. In the third incident, however, I was all by myself on the road.